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hello and welcome to technically speaking a podcast where scientists and engineers come together to chat about common interests share knowledge and satisfy some curiosity i'm Laura and in this episode i'm joined by Ghalia, Antonia and Ghinwa to talk about plastic and whether it's a good or a bad thing and i guess one of the reasons we're talking about this is a lot of talk about plastics in the ocean and in particular micro plastics uh angalia you work in the water industry so do you
encounter microplastics there well just to take a step back we use plat plastics a lot we use in our pipe work and and part of our treatment works so it's something that we definitely use all the time but when everyone else in the world use plastics and sometimes that can disintegrate and that can get washed up into our water systems and then that's when we have to deal with it and you can find micro plastics in less obvious places so like the paintings on the roads for example you know the stop
signs or whatever when it rains that goes into our drains and then that goes into our water systems but luckily our current treatment works actually kind of gets rid of those it's kind of an accident but it's kind of worked out well in our favor they get rid of most of the micro plastics so don't worry like it's still safe and good to drink but the problem that we have now is that okay cool it's safe and cool good to drink but we have the byproducts we have the
the waste water and the sludge and a lot of that it's got microplastics in it and we're not dealing with at the moment we're not too sure how we can take out those microplastics and and use it or recycle it or do something with it so it just goes back into our environment at the moment and that's kind of where we're like ah we need the plastics to get through the treatment works and get through the network and the system and at the end it's just like we have these
microplastics what are we going to do with them so it's definitely something that is a problem but the water is still safe to drink and accidentally our treatment work is doing quite well with that good so now so i guess the microplastics you're saying they get there because things certain things in different parts of human usage of things i was going to say the environment but that's not quite right no they degrade over time yeah again why you've got a background in chemistry
right do you have any thoughts about plastic degradation yeah i think one should shed the light on the different type of plastic actually because not every kind of plastic is producing the microplastic that you are encountering in the water industry galia if i understand what plastic most plastic are synthetic and some of them are are biodegradable or bio-derived ones so the synthetic one are either thermoset or thermoplastic ones so the thermoplastic ones we can
melt them and reuse them theoretically let's say everything is going well so these ones can be recycled so they don't have to end up in the environment as microplastic however the thermoset one we can use them only one time and then when they are heated or exposed to sun or whatever environmental conditions they degrade into microplastic and this is all the ones that end up in the environment however this is just talking theoretically because in reality we don't have one
type of plastic use and usually plastic is mixed with additives and all sorts of things so they don't end up being recycled and probably they end up in the in the environment and also talking about the biodegradable ones which are now on a big trend i think there's something that that should be thought about that these biopolymers or bioplastic they are modified to have new properties and then when they are modified also they may not be as biodegradable as they are in
as a raw material and then they may end up just being thrown in the environment and not recycled again so it's quite a complex thing to think about there's a lot to impact there around how do you get the chemistry right for a particular plastic for a particular application and i guess we'll we'll get into the details on that but uh antonia your your background might lend some more insight to this yes just following on from gimwa we have a lot of um plastic that is
the type that can be recycled chemically but logistically it isn't recycled and i think that's quite interesting so some statistics from the bbc in a recent article from this year is 16 of plastic waste is recycled to make new plastic 40 is sent to landfill 25 to incineration and 19 is dumped so it's interesting that we use a lot of was it thermoset or thermoplastic that was recyclable over plastic yeah yeah it's from a plastic that is recyclable yeah so if i if i just sort of run through
some of the household and numbers so on the bottom of plastic patching you often see this little light triangle and inside there's a number in it it's a labeling for what type of plastic was used and in my local area in manchester notice one and two are recycled on the curbside three four five six seven are not but three to six they're actually um firmer plastic it's just we don't have the facilities to recycle them um from the household so you know we were told if we
use these plastics they could be recycled and they're not a lot of people just assume that oh this is plastic we can just put in the recycling box that that says plastics i'm not sure how many people actually go through and like look for the number i think most people just throw the plastics in the recycling bin and think that they're doing a really good job yeah i've heard of this new um new terminology which is like an optimistic recycler or wishful recycler
that they kind of hope that it will get recycled but unfortunately because it depends on what kind of recycling plant there is some recycling plants don't have a person sorting it because the person sorting it is best at picking out the right type and picking out things that are going to contaminate the waste stream so you know anything that's got too much food anything that's got a lot of mixed materials like we were saying that often plastic is mixed with something else
they gotta pull those out as well you know uh coffee cups because they are coated paper can't be recycled and paper can't be recycled and plastic it's really it's hard as a person who wants to recycle isn't it you you want you want to put it in but you really shouldn't because it'll make it it basically they just dump an entire bag if they see too many contaminants in the first place you know too many things that shouldn't be recycled in that particular stream
it is more expensive for them to pick it out than to to go through with it and get a poorer quality material at the end yeah the one thing i find weird is plastic film a lot of my food it's where most of my plastic waste comes from is food packaging and a lot of it is like plastic films like dried beans come in plastic bags and things like that and we can't recycle that from what i've seen and it just it seems odd to me i try and eat less meat which means less solid plastic waste which
means more film and then that's not recyclable yeah so i think even like you know aluminium foil or tin foil the advice is before you put it in your recycling bin to scrunch it up because when it's the sheet it could just fly away off the off the heap so i think that might be what happens to the plastic film as well yeah that's what i'd read though yeah clog up machinery the heavier stuff is easier to process yeah i think the problem with the plastic is as i said when we have a
mixture of stuff all together so as thermoplastic by itself it is recyclable however it's rarely used as it is because there's always additive or ink or colors or whatever the or a mixture of polymers that make it less recyclable i think we like a lot of the facilities and most of the waste and the plastic waste actually from the us and europe are shipped to china china was the biggest country import for importing plastic and also countries like india or asian countries because they have
cheap labor and these people which are mostly women work on that sorting and segregation of plastic and therefore there's a chance for them to be recycled otherwise it's a pain to just you know have a pack of plastic and it's different colors different materials all packed together and you need to know what kind of plastic should go so what kind of cycling recycling facility and tony you said i think was it 16 of plastic is recycled it's made into new plastic but i've read there's like 30 to
40 million tons of plastic waste produced every year wow so that's quite a lot of plastic to be shipping around the world to go and recycle it i wonder how how useful it is what are the emissions co2 emissions from that shipping yeah side point but i mean plastic isn't all bad right so i'm i'm sitting in a room that has plastic pipes going to the heating system and plastic frames for the windows so i see quite a lot of plastic around me that is useful and it's going to be
there for a long time all right do you have a plastic water bottle as well not in this room just making sure that you're not using plastic water bottles that's all um we do get um oh actually i like i do have a plastic bottle in this room but it wasn't for water okay it was for orange juice and the alternative is to use tetra pack and tetra pack is not recyclable around here because i think uh guinea and tony both mentioned their composite so it's like cardboard with a plastic layer inside it
and i'd rather just buy some plastic and recycle it just like something that's not recyclable yeah yeah i was saying this big engineering project maybe i've mentioned it in one of the earlier episodes to upgrade my local water supply and get water from quite a long way away so i keep seeing all these really big blue plastic pipes sitting in fields that are ready to be buried underground to bring that water supply to me so a plastic is quite useful it depends on how you use
it and we sat here talking about this for maybe 10 minutes now i guess we should really define what the plastic is begin well with your chemistry background you the best person to define the plastic plastic are made out of polymers and polymers are long chain of monomers let's say a monomer is kind of a molecule formed of atoms and this monomer is repeated in a long chain and depending on what this monomer is formed of what atoms are forming this monomer and how long the chain is we can have
different type of plastic and different properties but also the plastic doesn't only include the polymer as i said but also all the additives to it to change its properties and make it more durable or softer or more rigid it depends on what we wanted to be used for so does that mean so i think of the plastic is something that's made out of carbon mostly is that not necessarily correct definition so i think it is correct to a big extent because polymers are made from fossil
fuel and fossil fuel is mainly carbon but then it depends um oh my god i forgot know the the word hydrocarbon it's just like it is hydrocarbon but then it depends on what atom you add to it or what ramification um you have out of the main molecule do you mean like functionalization functionalization exactly you might have to explain what functionalization is now i think there are only chemists that use that word in my context i start to forget my chemistry knowledge now been in engineering for a
long time so yeah so they are basically hydrocarbon because they come from fossil fuel but then they contain other atoms also and that what makes them different and they have different properties they're like squiggles on one of the ends you have a hydrogen and instead of a hydrogen you'd swap it out for a different molecule maybe like you might put oxygen in there or chlorine i was listening to a webinar about recycling plastic into hydrogen actually so they're breaking it down through
pyrolysis heating it up at high temperature without oxygen and pet is one of the most commonly recycled plastics i want to say in terms of like you know from a consumer perspective all our soft drink bottles are generally pet that's actually really bad to paralyze because it's got oxygen in the molecule and then you end up getting co2 and carbon monoxide which you then have to extract so actually saying that we recycle really well doesn't make her such a good feed stock
to make hydrogen and you say p e t that's gonna mispronounce right yeah they're both equally meaningless really unless you're a chemist and you can picture what that pet structure looks like i guess but yeah there's some carbon in there and there's some oxygen as well it's slightly more complicated than the little the squiggles the long chains of carbons that we've been talking about yeah i think um polyethylene might be the most simple one i think so yeah that's what i'd read so
that is literally that carbon backbone with the hydrogens around it yeah so it is basically hydrocarbon only the polyethylene one it doesn't have any heteroatom or anything like that yeah people can go and look this up if they're interested i think it's probably counterproductive of us trying to describe chemical structures using audio only might be a good um idea to give some examples of them what polyethylene makes so polyethylene you can have them in high density medium density low density
um but i think in high density if you think of like those milk cartons those are made out of polyethylene and plastic bags they can be made out of polyethylene so they are they high density polyethylene plastic bags they can be i just find that way because plastic bags are quite thin and they don't sound like a dense thing yeah it's quite counterproductive but yes they can be i guess yeah it's in a molecular level they're probably quite dense but not at the level we can pick them up and
crinkle them plastic bottles are probably the most widely recycled right you said they're made from pet at this point i would jump in with a statistic if i had one but you don't not today um so laura you're just saying that plastic bottles are the most widely recycled is that what you're saying that people often recycle their water bottles i believe so yeah that's what it looks like when you say you know you see those bins on the street that have got like a round hole for recycling and it's like
bottle sized with a pet thing it is widely recyclable because it is widely used and it is cheap to use and it has good properties therefore there's facilities to recycle but it's not it's not because it is more recyclable than pvc for example but it's just because it is widely used when we think about bottled water from a water industry perspective it's always a worry because we don't know how long those water bottles have been in direct sunlight for and so they do start
degrading it at some point and when when plastics start to like kind of like degrade does it become harder to recycle or does that not really affect its ability recycle i mean it's not good for you to drink the water after it's been in direct sunlight for ages and if the plastic bottle has been used over and over again it does start to degrade but does it affect its ability to recycle as well from my understanding degradation is just that the polymer chain is just reduced to a smaller size
but i'm not sure if the chemical composition uh changes the polymer i don't expect it to but i'm not quite sure about it okay but what i know that pet are very resistant to the uv light so for the degradation of a plastic so either it is biodegradable it means the bacteria can just kind of eat it and degrade it or it can be exposed to the uv light from the sun and it can degrade but i know that pet is more resistant to the uv light that's why it is used more in food
packaging rather than pvc and usually pvc is just used for let's say thick pipes or just rigid because it's a rigid material so it is used for rigid kind of application some some lingo we can use here is also that there's recycling post consumer and there's recycling in the in the manufacturer so a lot of recycling does happen in the manufacturer because they've just got one single stream they know what what material they have and so often plastic molding companies will if the product
doesn't come out so well they can just put it back in shred it up melt it reform it again so the challenge is actually post-consumer recycling you know once it's gone out into the world perhaps it has degraded under uv or been contaminated with biological things or you know had the additives has paint has um glue for packaging that kind of stuff that's that's where the bigger challenge is recycling it did anyone used to try and shrink crisp packets no the only way i'd shrink them was
because i wasn't allowed crisps that often so if i wanted more than one packet i'd shrink them up into really small small pieces and then throw them away so no one would see that that's the only reason why i was drinking christmas crisp packets when i was a kid how did you shrink them though well i think we put ours in the microwave but yeah you pour them in the oven as well what happened when you put them in the microwave they just shrinked yes so a crisp packet that what you sort of the
size of my palm would kind of shrink to maybe like the size of my thumb but retain all the text oh my god it's like miniaturizing yeah but it would go really stiff as well do you smell anything not really because you don't put it in for too long i would think it's a good point to like put some disclaimer in that we should we advise no one to do this i don't know i don't know if the chris pakist what about the ones with like you know when they're reflective on the inside
are those did you microwave those and what happened to those no i remember um i don't well maybe when i was a child chris buckets didn't have aluminium or whatever it is on the inside of them because i would imagine if it's metallic that would spark in a microwave right yeah yeah maybe you shouldn't do this yeah i'm gonna say i really don't think we should we should uh this was something of the past and we don't advise anyone to do it we did it on your behalf yeah maybe just watch a youtube
video instead that's a bit safer i've also accidentally shrunk a plastic drinks bottle many years ago because i wasn't really thinking about it and i hadn't considered the plastic shrinks when you heat it up and i was quickly trying to sanitize it so i poured some boiling water in from the kettle oh and then didn't have time to do anything else i just left the house with this tiny shrunken bottle of hot water it changed chemically as well like when it shrinks you've got to have some emission
that's why i ask about the smell if you smell anything well i said i kind of assumed that because that plastic is quite thin it's been stretched out somehow so all those long polymer chains have been kind of stretched and they're under tension so when it's heated up it just gives them enough energy where they can fall back up and go squiggly but are you totally wrong talking about entropy isn't it going to disorder whenever they can yeah but i guess because you said that a
lot of additives are put in so like polyethylene might not be just polyethylene it might be polyethylene some other chemical to change its properties so yeah who knows i'm still alive after drinking out of that one you actually drank it as well well you would have just kind of gone oh that's weird and then just left it but no you drank it it was in a hurry i didn't have time too much else i think someone was sitting outside in their car waiting to go quite a way down south through a
meeting so i don't really have time but from what i've read like some of the additives that come out with the plastics they come out in such small quantities the the the amounts at which or the rate at which you consume these various additives is probably okay yeah i was going to say unless you were just doing this in in gallons and liters every hour then you don't i don't think you should worry about now my tiny shrunken bottle of hot water dipped slowly through the course of a
day was fine just imagining you you you ha you said you have a house and there's some plastic in it now i'm just imagining like you also have a miniature house with all the miniature things from all them from all the miniature crisp packets and miniature water bottles what else are you gonna have now you've got to be wondering if you make a house out of lego bricks and stick it oh my god can you shrink it did you watch that movie about people shrinking the small size just to be to
live in a more sustainable world kind of and then if let's say you're just kind of a normal person with the money that you have you can afford to have like luxury life if you accept to be shrinked to like kind of a centimeter level uh yeah i take issue with the whole shrinking people down sci-fi thing because as we've just explained when you try and drink a plastic it travels open changes i don't think people can be shrunk so easily and still be people but [Laughter] i think that's really good
shrinking humans but imagine how less um feedstock we need then to just feed them and just have a nice life i think yeah we would we would need much less resources uh for nine for eight billions um i think we're eight billion at the moment aren't we i think this needs another podcast and it could be like kinwa's kind of utopia um yeah there's going to be something in here about plastic engineering and the difference between water pipes and water bottles so what do you guys know about
plastics engineering not the shrinking of people oh yeah so um i was i was talking about that um a polymer engineering um a module that i take that i took during my masters and um it was about reducing plastic waste by engineering new products that contain less material so rather than thinking about recycling the material or the plastic you can think about how to make a smaller water cup or a thinner water cup and that was this project this fun project on how to reduce the size of the
material but then maintaining the property so this is one thing we can think about when talking about plastic management let's say waste management you could look at when you make a product if you can keep it the same material so instead of mixing different materials so if you have a food container you can use the use the same base as well as the for the lid rather than you know some of our food containers and sort of more solid bottom and then film top if we didn't have a film top and had a
reusable top perhaps that would actually be a better use it might weigh more but it's more usable yeah i guess one of the things about single-use plastics is it means that until your say bottle of milk has been opened it's it's pretty because it's been sort of sterilized when it's packaged right and it will stay relatively sterile until you open it and expose it to the environment so i guess that's been one of the benefits of plastics of plastic packaging over the last few years is
that food lasts longer yeah it's actually quite a sort of inert way to store things yeah but i wonder if so if we're moving away from single-use plastic so you'd then have i can't quite imagine how you do this with milk cash like a big fat milk with a little tap on it so you go down the supermarket you just dump off some some milk maybe that was a bad example no it's i think it's a good example and i think it um we're not the infrastructure isn't there yet and so i know that there are some
like small shops um that do this like in the uk where you can go like with your own kind of glass bottles or whatever to like um top up and but it's it's expensive it's not it's not available for the masses but if i kind of like flip that and i think about other parts of the world when my family were growing up in like in the middle east they didn't have that much plastic so they'd go and they collect like their groceries but not in plastics and so i think it's it's really interesting that
where we've got to and kind of going backwards it's kind of really expensive that like actually to go back to how we used to collect our like food and drinks whatever is a really expensive process to go backwards and i think just talking about plastic as not a really bad thing i think one of the main reasons why people are talking about climate change in terms of in terms of energy rather than materials because i don't think we found i don't think there's an alternative
for plastic so far and talking about black plastic itself um i think it's quite environmentally friendly from one point of view if you see it like if you wanted transport let's say a pot of yogurt and they made out of glass they would be much heavier and they would need much more energy to be transported rather than having 10 pots of yogurt made out of plastic so it is kind of controversial in that in that way so it is environmentally kind of friendly but we got to think about how to use it
and how to manage it so we're sort of agreeing that it's not necessarily the plastic itself that's a problem per se it's what happens when people like us get hold of it yeah we got to have more infrastructure into recycling i think and because there's a lot of i think all of us we do a lot of effort into like reading the packages and sorting stuff into what kind of recycling bin but i'm not sure what's happening to it after after we do that effort as a consumer
and as let's say responsible citizens i think the government should do something about having more infrastructure that or facilities to recycle these plastics i think the challenge is economically what is the market for recycling plastic if we're gonna if we're gonna do that most recyclers do it because they can sell the their recycler so do we start adding a sort of cost to waste like increase how much it costs to landfill and so then people can save money by sending it to recycler because
then they can get recycling credits instead of you know carbon credits or or something i think this goes back to your point about though that it's not um you don't have plastics in their purest form like you add all these other i'm gonna say all the wrong words now both these additives and to color and et cetera so even if it gets to the point of recycling it's not necessarily possible and that's again just like the plastic but like we've talked about there are other things
there's like films and other things attached to the to the product so i think it's it is looking at like the designer's ability to kind of disable all this assemble i guess product so that's easier to like to to recycle so like i know like in the in the water industry it's a bit different because we end up with microplastics in the sludge there's a beautiful thing at the end and it's just a mixture of all these organic and inorganic sludgy kind of stuff and and it's a case
of does it make financial sense for me to like try and find the microplastics in there and once i do what am i going to do with that and there's a massive economic question around that like what is the benefit of doing this is the infrastructure available at the moment for us to to do that at the moment there isn't and kind of what is the incentive to do it i think it's it's a really difficult question because once you find the microplastics it's like okay like what you're talking about before
there are different varieties of plastic so it's not an easy thing to just but okay we can take them out and then put them elsewhere it's a difficult um thing what happens to the smudge currently this is my question that's true what'd you do so it depends it depends so for the waste water kind of stream um we can use it as fertilizers or you can put them in digesters and you can make um gas so you can use the gas for energy but um all you can use is fertilizers that there's a
variety of things we can do with them at the moment you don't want to put fertilizers full of microplastics though yeah but if it's a nut what would happen to them like it's not like the plants could use it could they or is there a chance we could put like um bacteria that eat plastics you know that's been that's been a hot research topic about designing enzymes around what they can break down including plastic um i don't know if it gets into the plants but there are two
parts of this there are other animals that can eat than like the everything around the fertilizer so they can then eat plastics and then often with fertilizers they get washed back into the river or the drains or something um and then that goes back into the system again um and so like when you have microplastics in in the in water in the rivers you have like the fish and everything else that they're consuming in the in the rivers they start taking in some of the plastics so it's definitely
something i wouldn't encourage but i don't really know how it goes i don't know how it can or can't go into the plants i'm not too familiar with that it's definitely something that we need to look into further though yeah apparently this has been so the area of microplastics has been investigated for almost 20 years by it sounds like an awful lot of researchers i guess it's worth defining what they are then i think less than five millimeters in length which to me sounds pretty big on
the scale of things because i tend to work with others i mean anything is bigger than a that's a good point yeah when you've been simulating a box of atoms it's like a few nanometers across for a few years you tend to think of everything as how many atoms but it's still not micro is it five millimeters it's not micrometer no i think i think micro just means it's smaller than something else so relative yeah and there's like a subclass of micro plastics it's like nanoplastics
and they are sort of micro scale they're one micrometer or less but not nano size they're there no because because if you were nano you'd be getting down to the scale of atoms okay but yeah those nanoplastics the one micrometer the smaller stay suspended in water so anything bigger would either sink or it would float and if it's suspended then that means that a whole load of other fishy things could access them and it sounds like a lot of the problem is um that they can sort of restrict how like
tiny sea creatures move more and it affects how they do things it sounds it sounds really interesting i hadn't really thought about it like this um but i mean ali you were saying there are lots of different compositions and lots of different ways they can get into different places and i think that's one of the problems with the research is there is so many different types of plastic with so many different additives that may leach out the the research even though it's been going clearly 20 years
still isn't entirely sure of what's going on um it sounds like what happens in the lab it probably isn't all that representative of what happens in the wider world which it's quite a common thing in science i think but apparently they are getting samples of actual plastics and that is i think you said that's a big problem in itself just finding the microplastics it's it's definitely a problem because um i think we've alluded to this before it's looking at something in a silo and it's
actually a lot bigger than it is so if i was going to start digging away at the sludge then we're going to find microplastics but then i'm also going to find heavy metals so what do i do with the heavy metals and then what do i do with all these other different minerals and chemicals materials that end up in the sludge and so it's looking at how we can we kind of more holistically look at the environment and the waste that we produce um i know like edward mentioned before about like um
movement of plastics it's much cheaper to move things in when it's plastic because it doesn't actually um cost that much in weight so there's like there's benefits too and like this so your carbon emissions when it comes to like movement is is much smaller and that's when we look at the environment we can't just look at like is this material bad or good i think it definitely needs a more holistic way of looking at it because if i can start tapping away at my my sludge in my in my
sewers in my in my um wastewater treatment plants then um then i should be looking at all the other materials i can extract and look at it and that maybe that's the best way to do it but if we're going to start tapping into that we need to understand like how we deal with all these other different materials and what's the most cost effective way of doing this sounds like there's a lot of science to do um given given that you're talking about microplastics this is a really weird story so i have
two pet rats and they're they're adorable but they eat a lot of plastic and yeah i've trained them to do things like they'll spit on the spot for food i've trained one of them to skateboard using a puppy amazing she also eats the skate podcast sometimes one one man's waste is another man's food but he can't be nutritious right she wants you to stole the milk bottle top because i was using that to teach her how to forage like hiding a pellet of food under the top and she had to figure
out how to flip it over and she also stole the milk bottle top took it into her cage i didn't know the entire thing overnight and then was pooping red plastic oh there was me sitting separating contaminated [Laughter] at least rat waste is solid that will be disposed of responsibly this i don't know what to do with it it's got microplastics in it probably use it as a fertilizer as gallium burn it just just burn it i don't think so i think the conclusion is that we get laura to all these
different treatment plants across the uk through all this sludge pick out these micro plastics and uh yeah we maybe burn it maybe that's the best thing to do yeah trained rats or burnings that that's the future isn't it yeah but it's the rats that are pooping it out so actually you still need laura to come and separate them it's just laura laura needs to go around just just attacking those that sludge so i'm i'm the solution to wade through how many what volume of sludge do you
want to wait i don't even know how many tons tons and tons no um i can't see that good luck the one time i've been to a waste treatment plant it the smell i've got quite a strong stomach normally but that smell was unpleasant that's a very polite way of saying it yeah i don't think me waiting too slow just a feasible solution thanks though damn it how many lauras would it take but we still don't know what to do with it once we find these microplastics what
are we doing with them but we know we've got it out the sludge at least that's true that's true one step at a time yeah moving away from from laura's um next career move wading through sludge i think it's quite clear though that we realize that there are limits to looking at plastics as the the solution to so many things and plastics have really helped us get to where we are are at the moment it's just now kind of understanding really like what is the best way to to manage plastics yeah i
mean i think the big thing around single-use plastics is plastic lasts for hundreds of years and so what's the point in using something so going back to my orange juice of consuming the orange juice and then throwing that bottle away and i recycle that but is there something better you could do than just recycling could i just take it back somewhere and get it refilled and then re-sterilized would that make more sense you know when we used to have um glass bottles for
milk the milk bottles would get collected you refill it and it's a single use it only ever gets used so i don't mean single use in that sense it gets used one time it only has one purpose so do we start getting loads of things that have a singular purpose or do we want our plastic to to be able to make new products but i think this is the whole thing about the fossil fuel industry isn't it they want a single use plastic because they are producing a lot and they want to consume it and
especially now like the fossil fuel industry is shifting towards a lot of facilities of producing plastic because they know the world is going towards more sustainable source of energy so probably the use of fossil fuel as a source of energy wouldn't be the one for the future so there's a lot of new industries just to make plastic so what we're going to do with all that plastic if we're going to use the plastic that we already have and recycle it i think it's not beneficial
economically for these industries so there's a clash over here between like environment and benefit of these big fossil fuel industries and where we want to stand i think i think there's still an argument to be had about whether or not we need we should dig up these fossil fuels out of the ground because not only do we burn them and then produce co2 if we don't extract them in the most efficient way then we actually accidentally leak methane in sierra which has even higher global warming
potential on a shorter time frame so should we just leave it in the ground we also have to go to various places to to extract it you know the damage that we could do to the environment in in that process is it worth it do we or do we continue our research into biological sources for classic making or maybe that can be a feature podcast episode alternative production methods for plastics that don't involve fossil fuels yeah also we we've not really touched on biodegradable plastic what happens do
they just break down into the organic compounds or yeah theoretically they do but because of all the additives to make them have a new properties i don't think the enzyme or the bacteria can digest them the same way they digest a raw kind of biodegradable plastic or polymer let's say so just imagine like if you take a piece of a tree which is a cellulose polymer so basically that can be degraded very well in the environment because the enzyme or the bacteria is going to digest it very
easily but then if you take that put it in a high concentration of caustic solution to just take the polymer out and then functionalize it a research is saying it's not as easy for the bacteria to reach out to that polymer or plastic and digest it the same way so does it need a particular bacterium to digest it or a particular enzyme from bacterium there's like special bacteria that eat special kind of polymer like a polyethylene haze or something yeah they said that there's new enzymes
or bacteria that can degrade polyester pet and pvc pvc well does that mean that you could set you can set this bacterium on the window frames in my head my window frames because that doesn't sound like a good thing yeah be sure it doesn't need something else though yeah i think we have already all the plastic feedstock we want for the coming 50 years if we just recycle everything and reuse it we don't need more that's an amazing flat but that is not happening for a reason
do we have enough energy to do it well we're having the energy to produce a fossil fuel in the first place and we have the the energy and the money to to make the plastic itself so why not uh that is one of the things i'd read that it requires more energy to recycle than it does to make it fresh but i don't know how true that is i see yeah it might be i think it's a i don't think it's black and white is that that's the general conclusion of most of our discussions is plastic good
or bad like it's not that black it's not black and white is it no but i think any plastic that's designed for long-term use like those water pipes that are being buried in the fields near me they can last for like 100 years or something decades yeah whereas again the single-use plastic that you believe in plastic bottles you you use it once but it'll still persist for like 100 years which i guess is why microplastics are so much interest because they're out in the environment
and they're difficult to get back but they're going to be there for a while and we don't know what they're going to do if you look at the plastic for example in the medical sector it's quite useful for hygienic purposes let's say now with the corvette all these threes are not reusable i think you'll use like the ppe but what do we do with all that you know we we have to incinerate it because it's hazardous waste so yeah yeah plastic it is a good thing in other industries
rather than the food industry in the food industry because we have a lot of packaging that's exactly the point i think there are so many benefits to plastics like you said when i do my like lateral flow test what's you've ever got covered or not i don't want anyone else to ever have to deal with that and it's it's easy then you can go and incinerate it and but i think it's definitely it's definitely useful a lot of industries and i guess it's just trying to work out
how can we manage the waste yeah and i guess that's probably quite a good summary of the conversation so that means i don't have to sum up which is great because i am starting to lose my voice uh i'm pretty sure i'm getting a cold so i think we'll probably leave it there because my voice is really starting to go yes yeah you should probably stop speaking thanks for that you've enjoyed this episode you can find us on twitter you can leave a comment on this episode or we do have an email
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